TL;DR
PT-141 (Bremelanotide) is a cyclic heptapeptide melanocortin receptor agonist with selectivity for MC3R and MC4R subtypes. Originally developed from alpha-MSH, it received FDA approval in 2019 as for a specific clinical indication. For research purposes, it remains one of the most important tool compounds for investigating melanocortin receptor pharmacology.
Research use only. PT-141 has not received FDA approval for any human therapeutic indication and is sold strictly for in-vitro laboratory research purposes.
What is PT-141?
PT-141 (Bremelanotide) is a cyclic heptapeptide melanocortin receptor agonist with selectivity for MC3R and MC4R subtypes. Originally developed from alpha-MSH, it received FDA approval in 2019 as for a specific clinical indication. For research purposes, it remains one of the most important tool compounds for investigating melanocortin receptor pharmacology.
Research-grade PT-141 is supplied as a lyophilized powder with batch-specific Certificate of Analysis verification at ≥99% purity by HPLC.
Molecular Properties
| Property | Value |
|---|---|
| Molecular formula | C₅₀H₆₈N₁₄O₁₀ |
| Molecular weight | 1,025.20 g/mol |
| Amino acid count | 7 |
| Purity standard | ≥99% (HPLC verified) |
| Lyophilized storage | -20°C, 24–36 months |
| Reconstitution vehicle | Bacteriostatic water (primary), 0.6% acetic acid or saline (alternative) |
Proposed Mechanisms of Action
Published preclinical research has proposed several complementary mechanisms through which PT-141 may exert observed effects in laboratory models. No single mechanism has been fully validated in human contexts.
MC3R and MC4R receptor activation
PT-141 activates melanocortin receptor subtypes 3 and 4 with negligible MC1R binding, producing receptor-subtype-specific downstream signaling.
cAMP-mediated signaling
Classical Gs-protein coupling with adenylyl cyclase activation and cAMP production in receptor-expressing cells.
CNS-mediated autonomic and arousal pathways
MC4R activation in hypothalamic nuclei modulates autonomic outflow and arousal circuitry in published rodent research.
Research Applications
Melanocortin receptor pharmacology
Dose-response, receptor binding, and downstream signaling studies across MC3R and MC4R-expressing cell lines and tissues.
Autonomic nervous system research
Studies examining cardiovascular parameters, thermoregulation, and autonomic outflow in rodent models.
Comparative melanocortin studies
Benchmark compound in studies comparing receptor-selective vs non-selective melanocortin analogs.
Storage and Reconstitution
- Lyophilized at -20°C in original sealed vial; typical shelf life 24–36 months.
- Reconstitution with bacteriostatic water (0.9% benzyl alcohol) is standard. Alternative vehicles include sterile saline or dilute acetic acid depending on experimental requirements.
- Reconstituted solution stored at 2–8°C, used within 7–28 days.
- Avoid repeated freeze-thaw of reconstituted peptide.
- Handling: Follow institutional biosafety protocols; use only in qualified research settings.
Regulatory Considerations
As of early 2026, PT-141 has no investigational human therapeutic indication. The peptide continues to be available for strictly in-vitro research purposes when properly labeled, sold to qualified researchers, and handled under appropriate institutional biosafety protocols. Researchers should consult current FDA guidance and institutional policies before acquiring any research peptide.
Research Gaps
Despite the substantial published literature on PT-141:
- Human pharmacokinetic and pharmacodynamic data remains limited.
- Proposed mechanisms require further validation in human-relevant systems.
- Long-term safety data across species is incomplete.
- Dose-response optimization for specific research applications continues to be an active research question.
- Independent cross-laboratory replication of specific findings is uneven across the literature.
These gaps represent ongoing research opportunities for careful, well-designed preclinical investigation using research-grade material with verified Certificate of Analysis.
Frequently Asked Questions
Is PT-141 approved for human use?
No. PT-141 has no investigational therapeutic indication. It is sold exclusively for in-vitro laboratory research in qualified research settings.
What purity standard should research-grade PT-141 meet?
Quality research-grade material should be ≥99% purity as verified by HPLC with a batch-specific Certificate of Analysis. Aureum Peptides provides COAs with every shipment and maintains a searchable COA portal.
How is PT-141 typically reconstituted for research?
Bacteriostatic water is the most common reconstitution vehicle. Alternative vehicles (sterile saline, dilute acetic acid) may be used depending on specific experimental protocols.
How long is reconstituted PT-141 stable?
Once reconstituted, the peptide is generally stored at 2–8°C and used within 7–28 days depending on specific handling and vehicle. Avoid repeated freeze-thaw cycles.
Where can I verify the Certificate of Analysis for my batch?
Aureum Peptides includes a batch-specific COA with every shipment and maintains an online COA portal accessible using the batch number printed on your vial.
References
- Molinoff PB et al. Ann N Y Acad Sci. 2003.
- Pfaus JG et al. Pharmacol Biochem Behav. 2004.
- Diamond LE et al. 2006.
- Kingsberg SA et al. Obstet Gynecol. 2019.
- Wessells H et al. 2000.
(Reference list abbreviated. Full bibliography with DOIs available on request.)
Shop Research-Grade PT-141
Order research-grade PT-141 from Aureum Peptides: PT-141 product page
All peptides ship with batch-specific Certificate of Analysis, ≥99% purity verification, and cold-chain logistics. Same-day dispatch on orders placed before 2:00 PM EST.
Disclaimer: This article summarizes published preclinical research for educational purposes to support qualified research activities. The information herein does not constitute research information, therapeutic claims, or recommendations for human use. PT-141 is not approved by the FDA for any therapeutic indication. Always consult institutional policies and applicable regulations when conducting research with peptides.
Last reviewed: 2026-04-21
Author: Aureum Peptides Scientific Writing Team
Category: Neuropeptide Research
Tags: PT-141, Bremelanotide, melanocortin, MC3R, MC4R
